The present invention relates to a new and distinct cultivar of Penstemon given the name ‘TNPENHR’. Penstemon is in the family Scrophulariaceae. Penstemon ‘TNPENHR’ originated as open pollinated seed collected from Penstemon ‘262-1’, an unnamed, unpatented, proprietary plant. It was part of a controlled breeding program to create a compact, upright, medium-small-size-habit, reblooming, and hardy series. This seedling was selected for its medium-size red flowers in dense clusters; long bloom time; good rebloom; compact, upright, well-branched habit with multiple crowns from the base; vigor; and clean, attractive look. It is an ideal plant for a sunny border in full sun.